Hearing aids are portable hearing instruments which serve to provide hearing assistance to the hearing-impaired. In order to accommodate the multiplicity of individual requirements, different designs of hearing aid are provided, including behind-the-ear (BTE) and in-the-ear (ITE) hearing aids, e.g. concha or completely-in-canal (CIC) instruments. The hearing devices cited by way of example are worn on the outer ear or in the auditory canal. However, bone conduction hearing aids, implantable or vibrotactile hearing aids are also commercially available. In these cases the damaged hearing is stimulated either mechanically or electrically.
The basic components of a hearing aid are essentially an input transducer, an amplifier and an output transducer. The input transducer is generally a sound pickup device, e.g. a microphone, and/or an electromagnetic pickup such as an induction coil. The output transducer is mainly implemented as an electroacoustic transducer, e.g. a miniature loudspeaker, or as an electromechanical transducer such as a bone conduction receiver. The amplifier is usually incorporated in a signal processing unit.
This basic design is shown in FIG. 1 using the example of a behind-the-ear hearing aid. Installed in a hearing aid housing 1 for wearing behind the ear are one or more microphones 2 for picking up sound from the environment. A signal processing unit 3 which is likewise incorporated in the hearing aid housing 1 processes the microphone signals and amplifies them. The output signal of the signal processing unit 3 is transmitted to a loudspeaker or receiver 4 which outputs an audible signal. The sound is in some cases transmitted to the wearer's eardrum via a sound tube which is fixed in the auditory canal using an earmold. The hearing aid and in particular the signal processing unit 3 are powered by a battery 5 which is likewise incorporated in the hearing aid housing 1.
Also specifically known are receiver-in-canal (RIC) instruments which have a receiver unit for insertion into the auditory canal. These are fitted using not only so-called standardized soft ear tips but also using custom-made ear shells, i.e. earmolds, the receivers being inserted into the standardized or custom ear shell. When removing the receiver unit from the auditory canal, the user typically grips the receiver unit by the receiver or by the signal wire connected thereto. In the case of an earmold that is relatively firmly seated in the auditory canal, a high retaining force between the receiver and the earmold is necessary in order to prevent the entire unit from being pulled apart when the receiver unit is removed from the auditory canal. This high retaining force in turn means that the receiver unit can only be pushed out of the ear shell or more specifically earmold with the aid of a tool (“cherry stone remover”) for cleaning purposes and general replacement of the side facing the eardrum (inside of the ear shell). In this process the cerumen protection device disposed in the sound outlet opening is frequently destroyed. In addition, after many replacements both the receiver and the ear shell or more specifically a corresponding adapter become worn or damaged over time. This means that the seal tightness between the receiver and the ear shell is reduced, possibly resulting not only in soiling of the receiver but also in audible feedback.
The publication WO 2004/025990 A1 discloses a hearing aid with an external receiver module. The receiver module consists of an earmold to which a receiver is attached using a specially shaped fixing element which, on the one hand, holds the receiver and, on the other, is screwed to the earmold.
In addition, the publication DE 10 2004 016 577 A1 discloses a headset with hearing aid functionality. An earmold is connected to the headset module using a snap-in or bayonet fitting.